diff options
Diffstat (limited to 'pkg')
28 files changed, 149 insertions, 458 deletions
diff --git a/pkg/sentry/socket/netfilter/tcp_matcher.go b/pkg/sentry/socket/netfilter/tcp_matcher.go index 55c0f04f3..ff1cfd8f6 100644 --- a/pkg/sentry/socket/netfilter/tcp_matcher.go +++ b/pkg/sentry/socket/netfilter/tcp_matcher.go @@ -121,13 +121,12 @@ func (tm *TCPMatcher) Match(hook stack.Hook, pkt stack.PacketBuffer, interfaceNa tcpHeader = header.TCP(pkt.TransportHeader) } else { // The TCP header hasn't been parsed yet. We have to do it here. - hdr, ok := pkt.Data.PullUp(header.TCPMinimumSize) - if !ok { + if len(pkt.Data.First()) < header.TCPMinimumSize { // There's no valid TCP header here, so we hotdrop the // packet. return false, true } - tcpHeader = header.TCP(hdr) + tcpHeader = header.TCP(pkt.Data.First()) } // Check whether the source and destination ports are within the diff --git a/pkg/sentry/socket/netfilter/udp_matcher.go b/pkg/sentry/socket/netfilter/udp_matcher.go index 04d03d494..3359418c1 100644 --- a/pkg/sentry/socket/netfilter/udp_matcher.go +++ b/pkg/sentry/socket/netfilter/udp_matcher.go @@ -120,13 +120,12 @@ func (um *UDPMatcher) Match(hook stack.Hook, pkt stack.PacketBuffer, interfaceNa udpHeader = header.UDP(pkt.TransportHeader) } else { // The UDP header hasn't been parsed yet. We have to do it here. - hdr, ok := pkt.Data.PullUp(header.UDPMinimumSize) - if !ok { + if len(pkt.Data.First()) < header.UDPMinimumSize { // There's no valid UDP header here, so we hotdrop the // packet. return false, true } - udpHeader = header.UDP(hdr) + udpHeader = header.UDP(pkt.Data.First()) } // Check whether the source and destination ports are within the diff --git a/pkg/tcpip/buffer/view.go b/pkg/tcpip/buffer/view.go index f01217c91..8ec5d5d5c 100644 --- a/pkg/tcpip/buffer/view.go +++ b/pkg/tcpip/buffer/view.go @@ -77,8 +77,7 @@ func NewVectorisedView(size int, views []View) VectorisedView { return VectorisedView{views: views, size: size} } -// TrimFront removes the first "count" bytes of the vectorised view. It panics -// if count > vv.Size(). +// TrimFront removes the first "count" bytes of the vectorised view. func (vv *VectorisedView) TrimFront(count int) { for count > 0 && len(vv.views) > 0 { if count < len(vv.views[0]) { @@ -87,7 +86,7 @@ func (vv *VectorisedView) TrimFront(count int) { return } count -= len(vv.views[0]) - vv.removeFirst() + vv.RemoveFirst() } } @@ -105,7 +104,7 @@ func (vv *VectorisedView) Read(v View) (copied int, err error) { count -= len(vv.views[0]) copy(v[copied:], vv.views[0]) copied += len(vv.views[0]) - vv.removeFirst() + vv.RemoveFirst() } if copied == 0 { return 0, io.EOF @@ -127,7 +126,7 @@ func (vv *VectorisedView) ReadToVV(dstVV *VectorisedView, count int) (copied int count -= len(vv.views[0]) dstVV.AppendView(vv.views[0]) copied += len(vv.views[0]) - vv.removeFirst() + vv.RemoveFirst() } return copied } @@ -163,37 +162,22 @@ func (vv *VectorisedView) Clone(buffer []View) VectorisedView { return VectorisedView{views: append(buffer[:0], vv.views...), size: vv.size} } -// PullUp returns the first "count" bytes of the vectorised view. If those -// bytes aren't already contiguous inside the vectorised view, PullUp will -// reallocate as needed to make them contiguous. PullUp fails and returns false -// when count > vv.Size(). -func (vv *VectorisedView) PullUp(count int) (View, bool) { +// First returns the first view of the vectorised view. +func (vv *VectorisedView) First() View { if len(vv.views) == 0 { - return nil, count == 0 - } - if count <= len(vv.views[0]) { - return vv.views[0][:count], true - } - if count > vv.size { - return nil, false + return nil } + return vv.views[0] +} - newFirst := NewView(count) - i := 0 - for offset := 0; offset < count; i++ { - copy(newFirst[offset:], vv.views[i]) - if count-offset < len(vv.views[i]) { - vv.views[i].TrimFront(count - offset) - break - } - offset += len(vv.views[i]) - vv.views[i] = nil +// RemoveFirst removes the first view of the vectorised view. +func (vv *VectorisedView) RemoveFirst() { + if len(vv.views) == 0 { + return } - // We're guaranteed that i > 0, since count is too large for the first - // view. - vv.views[i-1] = newFirst - vv.views = vv.views[i-1:] - return newFirst, true + vv.size -= len(vv.views[0]) + vv.views[0] = nil + vv.views = vv.views[1:] } // Size returns the size in bytes of the entire content stored in the vectorised view. @@ -241,10 +225,3 @@ func (vv *VectorisedView) Readers() []bytes.Reader { } return readers } - -// removeFirst panics when len(vv.views) < 1. -func (vv *VectorisedView) removeFirst() { - vv.size -= len(vv.views[0]) - vv.views[0] = nil - vv.views = vv.views[1:] -} diff --git a/pkg/tcpip/buffer/view_test.go b/pkg/tcpip/buffer/view_test.go index c56795c7b..106e1994c 100644 --- a/pkg/tcpip/buffer/view_test.go +++ b/pkg/tcpip/buffer/view_test.go @@ -16,7 +16,6 @@ package buffer import ( - "bytes" "reflect" "testing" ) @@ -371,115 +370,3 @@ func TestVVRead(t *testing.T) { }) } } - -var pullUpTestCases = []struct { - comment string - in VectorisedView - count int - want []byte - result VectorisedView - ok bool -}{ - { - comment: "simple case", - in: vv(2, "12"), - count: 1, - want: []byte("1"), - result: vv(2, "12"), - ok: true, - }, - { - comment: "entire View", - in: vv(2, "1", "2"), - count: 1, - want: []byte("1"), - result: vv(2, "1", "2"), - ok: true, - }, - { - comment: "spanning across two Views", - in: vv(3, "1", "23"), - count: 2, - want: []byte("12"), - result: vv(3, "12", "3"), - ok: true, - }, - { - comment: "spanning across all Views", - in: vv(5, "1", "23", "45"), - count: 5, - want: []byte("12345"), - result: vv(5, "12345"), - ok: true, - }, - { - comment: "count = 0", - in: vv(1, "1"), - count: 0, - want: []byte{}, - result: vv(1, "1"), - ok: true, - }, - { - comment: "count = size", - in: vv(1, "1"), - count: 1, - want: []byte("1"), - result: vv(1, "1"), - ok: true, - }, - { - comment: "count too large", - in: vv(3, "1", "23"), - count: 4, - want: nil, - result: vv(3, "1", "23"), - ok: false, - }, - { - comment: "empty vv", - in: vv(0, ""), - count: 1, - want: nil, - result: vv(0, ""), - ok: false, - }, - { - comment: "empty vv, count = 0", - in: vv(0, ""), - count: 0, - want: nil, - result: vv(0, ""), - ok: true, - }, - { - comment: "empty views", - in: vv(3, "", "1", "", "23"), - count: 2, - want: []byte("12"), - result: vv(3, "12", "3"), - ok: true, - }, -} - -func TestPullUp(t *testing.T) { - for _, c := range pullUpTestCases { - got, ok := c.in.PullUp(c.count) - - // Is the return value right? - if ok != c.ok { - t.Errorf("Test %q failed when calling PullUp(%d) on %v. Got an ok of %t. Want %t", - c.comment, c.count, c.in, ok, c.ok) - } - if bytes.Compare(got, View(c.want)) != 0 { - t.Errorf("Test %q failed when calling PullUp(%d) on %v. Got %v. Want %v", - c.comment, c.count, c.in, got, c.want) - } - - // Is the underlying structure right? - if !reflect.DeepEqual(c.in, c.result) { - t.Errorf("Test %q failed when calling PullUp(%d). Got vv with structure %v. Wanted %v", - c.comment, c.count, c.in, c.result) - } - } -} diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go index 073c84ef9..1e2255bfa 100644 --- a/pkg/tcpip/link/loopback/loopback.go +++ b/pkg/tcpip/link/loopback/loopback.go @@ -98,13 +98,13 @@ func (e *endpoint) WritePackets(*stack.Route, *stack.GSO, stack.PacketBufferList // WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket. func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { - // There should be an ethernet header at the beginning of vv. - hdr, ok := vv.PullUp(header.EthernetMinimumSize) - if !ok { - // Reject the packet if it's shorter than an ethernet header. + // Reject the packet if it's shorter than an ethernet header. + if vv.Size() < header.EthernetMinimumSize { return tcpip.ErrBadAddress } - linkHeader := header.Ethernet(hdr) + + // There should be an ethernet header at the beginning of vv. + linkHeader := header.Ethernet(vv.First()[:header.EthernetMinimumSize]) vv.TrimFront(len(linkHeader)) e.dispatcher.DeliverNetworkPacket(e, "" /* remote */, "" /* local */, linkHeader.Type(), stack.PacketBuffer{ Data: vv, diff --git a/pkg/tcpip/link/rawfile/BUILD b/pkg/tcpip/link/rawfile/BUILD index 9cc08d0e2..14b527bc2 100644 --- a/pkg/tcpip/link/rawfile/BUILD +++ b/pkg/tcpip/link/rawfile/BUILD @@ -1,4 +1,4 @@ -load("//tools:defs.bzl", "go_library", "go_test") +load("//tools:defs.bzl", "go_library") package(licenses = ["notice"]) @@ -18,10 +18,3 @@ go_library( "@org_golang_x_sys//unix:go_default_library", ], ) - -go_test( - name = "rawfile_test", - size = "small", - srcs = ["rawfile_test.go"], - library = ":rawfile", -) diff --git a/pkg/tcpip/link/rawfile/rawfile_test.go b/pkg/tcpip/link/rawfile/rawfile_test.go deleted file mode 100644 index 8f14ba761..000000000 --- a/pkg/tcpip/link/rawfile/rawfile_test.go +++ /dev/null @@ -1,46 +0,0 @@ -// Copyright 2020 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// +build linux - -package rawfile - -import ( - "syscall" - "testing" -) - -func TestNonBlockingWrite3ZeroLength(t *testing.T) { - fd, err := syscall.Open("/dev/null", syscall.O_WRONLY, 0) - if err != nil { - t.Fatalf("failed to open /dev/null: %v", err) - } - defer syscall.Close(fd) - - if err := NonBlockingWrite3(fd, []byte{}, []byte{0}, nil); err != nil { - t.Fatalf("failed to write: %v", err) - } -} - -func TestNonBlockingWrite3Nil(t *testing.T) { - fd, err := syscall.Open("/dev/null", syscall.O_WRONLY, 0) - if err != nil { - t.Fatalf("failed to open /dev/null: %v", err) - } - defer syscall.Close(fd) - - if err := NonBlockingWrite3(fd, nil, []byte{0}, nil); err != nil { - t.Fatalf("failed to write: %v", err) - } -} diff --git a/pkg/tcpip/link/rawfile/rawfile_unsafe.go b/pkg/tcpip/link/rawfile/rawfile_unsafe.go index 92efd0bf8..44e25d475 100644 --- a/pkg/tcpip/link/rawfile/rawfile_unsafe.go +++ b/pkg/tcpip/link/rawfile/rawfile_unsafe.go @@ -76,13 +76,9 @@ func NonBlockingWrite3(fd int, b1, b2, b3 []byte) *tcpip.Error { // We have two buffers. Build the iovec that represents them and issue // a writev syscall. - var base *byte - if len(b1) > 0 { - base = &b1[0] - } iovec := [3]syscall.Iovec{ { - Base: base, + Base: &b1[0], Len: uint64(len(b1)), }, { diff --git a/pkg/tcpip/link/sharedmem/sharedmem_test.go b/pkg/tcpip/link/sharedmem/sharedmem_test.go index 33f640b85..27ea3f531 100644 --- a/pkg/tcpip/link/sharedmem/sharedmem_test.go +++ b/pkg/tcpip/link/sharedmem/sharedmem_test.go @@ -674,7 +674,7 @@ func TestSimpleReceive(t *testing.T) { // Wait for packet to be received, then check it. c.waitForPackets(1, time.After(5*time.Second), "Timeout waiting for packet") c.mu.Lock() - rcvd := []byte(c.packets[0].vv.ToView()) + rcvd := []byte(c.packets[0].vv.First()) c.packets = c.packets[:0] c.mu.Unlock() diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go index 0799c8f4d..be2537a82 100644 --- a/pkg/tcpip/link/sniffer/sniffer.go +++ b/pkg/tcpip/link/sniffer/sniffer.go @@ -171,7 +171,11 @@ func (e *endpoint) GSOMaxSize() uint32 { func (e *endpoint) dumpPacket(prefix string, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { writer := e.writer if writer == nil && atomic.LoadUint32(&LogPackets) == 1 { - logPacket(prefix, protocol, pkt, gso) + first := pkt.Header.View() + if len(first) == 0 { + first = pkt.Data.First() + } + logPacket(prefix, protocol, first, gso) } if writer != nil && atomic.LoadUint32(&LogPacketsToPCAP) == 1 { totalLength := pkt.Header.UsedLength() + pkt.Data.Size() @@ -234,7 +238,7 @@ func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { // Wait implements stack.LinkEndpoint.Wait. func (e *endpoint) Wait() { e.lower.Wait() } -func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer, gso *stack.GSO) { +func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.View, gso *stack.GSO) { // Figure out the network layer info. var transProto uint8 src := tcpip.Address("unknown") @@ -243,49 +247,28 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P size := uint16(0) var fragmentOffset uint16 var moreFragments bool - - // Create a clone of pkt, including any headers if present. Avoid allocating - // backing memory for the clone. - views := [8]buffer.View{} - vv := buffer.NewVectorisedView(0, views[:0]) - vv.AppendView(pkt.Header.View()) - vv.Append(pkt.Data) - switch protocol { case header.IPv4ProtocolNumber: - hdr, ok := vv.PullUp(header.IPv4MinimumSize) - if !ok { - return - } - ipv4 := header.IPv4(hdr) + ipv4 := header.IPv4(b) fragmentOffset = ipv4.FragmentOffset() moreFragments = ipv4.Flags()&header.IPv4FlagMoreFragments == header.IPv4FlagMoreFragments src = ipv4.SourceAddress() dst = ipv4.DestinationAddress() transProto = ipv4.Protocol() size = ipv4.TotalLength() - uint16(ipv4.HeaderLength()) - vv.TrimFront(int(ipv4.HeaderLength())) + b = b[ipv4.HeaderLength():] id = int(ipv4.ID()) case header.IPv6ProtocolNumber: - hdr, ok := vv.PullUp(header.IPv6MinimumSize) - if !ok { - return - } - ipv6 := header.IPv6(hdr) + ipv6 := header.IPv6(b) src = ipv6.SourceAddress() dst = ipv6.DestinationAddress() transProto = ipv6.NextHeader() size = ipv6.PayloadLength() - vv.TrimFront(header.IPv6MinimumSize) + b = b[header.IPv6MinimumSize:] case header.ARPProtocolNumber: - hdr, ok := vv.PullUp(header.ARPSize) - if !ok { - return - } - vv.TrimFront(header.ARPSize) - arp := header.ARP(hdr) + arp := header.ARP(b) log.Infof( "%s arp %v (%v) -> %v (%v) valid:%v", prefix, @@ -301,7 +284,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P // We aren't guaranteed to have a transport header - it's possible for // writes via raw endpoints to contain only network headers. - if minSize, ok := transportProtocolMinSizes[tcpip.TransportProtocolNumber(transProto)]; ok && vv.Size() < minSize { + if minSize, ok := transportProtocolMinSizes[tcpip.TransportProtocolNumber(transProto)]; ok && len(b) < minSize { log.Infof("%s %v -> %v transport protocol: %d, but no transport header found (possible raw packet)", prefix, src, dst, transProto) return } @@ -314,11 +297,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P switch tcpip.TransportProtocolNumber(transProto) { case header.ICMPv4ProtocolNumber: transName = "icmp" - hdr, ok := vv.PullUp(header.ICMPv4MinimumSize) - if !ok { - break - } - icmp := header.ICMPv4(hdr) + icmp := header.ICMPv4(b) icmpType := "unknown" if fragmentOffset == 0 { switch icmp.Type() { @@ -351,11 +330,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P case header.ICMPv6ProtocolNumber: transName = "icmp" - hdr, ok := vv.PullUp(header.ICMPv6MinimumSize) - if !ok { - break - } - icmp := header.ICMPv6(hdr) + icmp := header.ICMPv6(b) icmpType := "unknown" switch icmp.Type() { case header.ICMPv6DstUnreachable: @@ -386,11 +361,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P case header.UDPProtocolNumber: transName = "udp" - hdr, ok := vv.PullUp(header.UDPMinimumSize) - if !ok { - break - } - udp := header.UDP(hdr) + udp := header.UDP(b) if fragmentOffset == 0 && len(udp) >= header.UDPMinimumSize { srcPort = udp.SourcePort() dstPort = udp.DestinationPort() @@ -400,11 +371,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.P case header.TCPProtocolNumber: transName = "tcp" - hdr, ok := vv.PullUp(header.TCPMinimumSize) - if !ok { - break - } - tcp := header.TCP(hdr) + tcp := header.TCP(b) if fragmentOffset == 0 && len(tcp) >= header.TCPMinimumSize { offset := int(tcp.DataOffset()) if offset < header.TCPMinimumSize { diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go index cf73a939e..7acbfa0a8 100644 --- a/pkg/tcpip/network/arp/arp.go +++ b/pkg/tcpip/network/arp/arp.go @@ -93,10 +93,7 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuf } func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { - v, ok := pkt.Data.PullUp(header.ARPSize) - if !ok { - return - } + v := pkt.Data.First() h := header.ARP(v) if !h.IsValid() { return diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go index 4cbefe5ab..c4bf1ba5c 100644 --- a/pkg/tcpip/network/ipv4/icmp.go +++ b/pkg/tcpip/network/ipv4/icmp.go @@ -25,11 +25,7 @@ import ( // used to find out which transport endpoint must be notified about the ICMP // packet. func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.PacketBuffer) { - h, ok := pkt.Data.PullUp(header.IPv4MinimumSize) - if !ok { - return - } - hdr := header.IPv4(h) + h := header.IPv4(pkt.Data.First()) // We don't use IsValid() here because ICMP only requires that the IP // header plus 8 bytes of the transport header be included. So it's @@ -38,12 +34,12 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack. // // Drop packet if it doesn't have the basic IPv4 header or if the // original source address doesn't match the endpoint's address. - if hdr.SourceAddress() != e.id.LocalAddress { + if len(h) < header.IPv4MinimumSize || h.SourceAddress() != e.id.LocalAddress { return } - hlen := int(hdr.HeaderLength()) - if pkt.Data.Size() < hlen || hdr.FragmentOffset() != 0 { + hlen := int(h.HeaderLength()) + if pkt.Data.Size() < hlen || h.FragmentOffset() != 0 { // We won't be able to handle this if it doesn't contain the // full IPv4 header, or if it's a fragment not at offset 0 // (because it won't have the transport header). @@ -52,15 +48,15 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack. // Skip the ip header, then deliver control message. pkt.Data.TrimFront(hlen) - p := hdr.TransportProtocol() - e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, hdr.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt) + p := h.TransportProtocol() + e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, h.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt) } func (e *endpoint) handleICMP(r *stack.Route, pkt stack.PacketBuffer) { stats := r.Stats() received := stats.ICMP.V4PacketsReceived - v, ok := pkt.Data.PullUp(header.ICMPv4MinimumSize) - if !ok { + v := pkt.Data.First() + if len(v) < header.ICMPv4MinimumSize { received.Invalid.Increment() return } diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go index 17202cc7a..104aafbed 100644 --- a/pkg/tcpip/network/ipv4/ipv4.go +++ b/pkg/tcpip/network/ipv4/ipv4.go @@ -328,11 +328,7 @@ func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.Packe func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuffer) *tcpip.Error { // The packet already has an IP header, but there are a few required // checks. - h, ok := pkt.Data.PullUp(header.IPv4MinimumSize) - if !ok { - return tcpip.ErrInvalidOptionValue - } - ip := header.IPv4(h) + ip := header.IPv4(pkt.Data.First()) if !ip.IsValid(pkt.Data.Size()) { return tcpip.ErrInvalidOptionValue } @@ -382,11 +378,7 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuf // HandlePacket is called by the link layer when new ipv4 packets arrive for // this endpoint. func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { - headerView, ok := pkt.Data.PullUp(header.IPv4MinimumSize) - if !ok { - r.Stats().IP.MalformedPacketsReceived.Increment() - return - } + headerView := pkt.Data.First() h := header.IPv4(headerView) if !h.IsValid(pkt.Data.Size()) { r.Stats().IP.MalformedPacketsReceived.Increment() diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go index bdf3a0d25..b68983d10 100644 --- a/pkg/tcpip/network/ipv6/icmp.go +++ b/pkg/tcpip/network/ipv6/icmp.go @@ -28,11 +28,7 @@ import ( // used to find out which transport endpoint must be notified about the ICMP // packet. func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.PacketBuffer) { - h, ok := pkt.Data.PullUp(header.IPv6MinimumSize) - if !ok { - return - } - hdr := header.IPv6(h) + h := header.IPv6(pkt.Data.First()) // We don't use IsValid() here because ICMP only requires that up to // 1280 bytes of the original packet be included. So it's likely that it @@ -40,21 +36,17 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack. // // Drop packet if it doesn't have the basic IPv6 header or if the // original source address doesn't match the endpoint's address. - if hdr.SourceAddress() != e.id.LocalAddress { + if len(h) < header.IPv6MinimumSize || h.SourceAddress() != e.id.LocalAddress { return } // Skip the IP header, then handle the fragmentation header if there // is one. pkt.Data.TrimFront(header.IPv6MinimumSize) - p := hdr.TransportProtocol() + p := h.TransportProtocol() if p == header.IPv6FragmentHeader { - f, ok := pkt.Data.PullUp(header.IPv6FragmentHeaderSize) - if !ok { - return - } - fragHdr := header.IPv6Fragment(f) - if !fragHdr.IsValid() || fragHdr.FragmentOffset() != 0 { + f := header.IPv6Fragment(pkt.Data.First()) + if !f.IsValid() || f.FragmentOffset() != 0 { // We can't handle fragments that aren't at offset 0 // because they don't have the transport headers. return @@ -63,19 +55,19 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack. // Skip fragmentation header and find out the actual protocol // number. pkt.Data.TrimFront(header.IPv6FragmentHeaderSize) - p = fragHdr.TransportProtocol() + p = f.TransportProtocol() } // Deliver the control packet to the transport endpoint. - e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, hdr.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt) + e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, h.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt) } func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.PacketBuffer, hasFragmentHeader bool) { stats := r.Stats().ICMP sent := stats.V6PacketsSent received := stats.V6PacketsReceived - v, ok := pkt.Data.PullUp(header.ICMPv6HeaderSize) - if !ok { + v := pkt.Data.First() + if len(v) < header.ICMPv6MinimumSize { received.Invalid.Increment() return } @@ -84,9 +76,11 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P // Validate ICMPv6 checksum before processing the packet. // + // Only the first view in vv is accounted for by h. To account for the + // rest of vv, a shallow copy is made and the first view is removed. // This copy is used as extra payload during the checksum calculation. payload := pkt.Data.Clone(nil) - payload.TrimFront(len(h)) + payload.RemoveFirst() if got, want := h.Checksum(), header.ICMPv6Checksum(h, iph.SourceAddress(), iph.DestinationAddress(), payload); got != want { received.Invalid.Increment() return @@ -107,40 +101,34 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P switch h.Type() { case header.ICMPv6PacketTooBig: received.PacketTooBig.Increment() - hdr, ok := pkt.Data.PullUp(header.ICMPv6PacketTooBigMinimumSize) - if !ok { + if len(v) < header.ICMPv6PacketTooBigMinimumSize { received.Invalid.Increment() return } pkt.Data.TrimFront(header.ICMPv6PacketTooBigMinimumSize) - mtu := header.ICMPv6(hdr).MTU() + mtu := h.MTU() e.handleControl(stack.ControlPacketTooBig, calculateMTU(mtu), pkt) case header.ICMPv6DstUnreachable: received.DstUnreachable.Increment() - hdr, ok := pkt.Data.PullUp(header.ICMPv6DstUnreachableMinimumSize) - if !ok { + if len(v) < header.ICMPv6DstUnreachableMinimumSize { received.Invalid.Increment() return } pkt.Data.TrimFront(header.ICMPv6DstUnreachableMinimumSize) - switch header.ICMPv6(hdr).Code() { + switch h.Code() { case header.ICMPv6PortUnreachable: e.handleControl(stack.ControlPortUnreachable, 0, pkt) } case header.ICMPv6NeighborSolicit: received.NeighborSolicit.Increment() - if pkt.Data.Size() < header.ICMPv6NeighborSolicitMinimumSize || !isNDPValid() { + if len(v) < header.ICMPv6NeighborSolicitMinimumSize || !isNDPValid() { received.Invalid.Increment() return } - // The remainder of payload must be only the neighbor solicitation, so - // payload.ToView() always returns the solicitation. Per RFC 6980 section 5, - // NDP messages cannot be fragmented. Also note that in the common case NDP - // datagrams are very small and ToView() will not incur allocations. - ns := header.NDPNeighborSolicit(payload.ToView()) + ns := header.NDPNeighborSolicit(h.NDPPayload()) it, err := ns.Options().Iter(true) if err != nil { // If we have a malformed NDP NS option, drop the packet. @@ -298,16 +286,12 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P case header.ICMPv6NeighborAdvert: received.NeighborAdvert.Increment() - if pkt.Data.Size() < header.ICMPv6NeighborAdvertSize || !isNDPValid() { + if len(v) < header.ICMPv6NeighborAdvertSize || !isNDPValid() { received.Invalid.Increment() return } - // The remainder of payload must be only the neighbor advertisement, so - // payload.ToView() always returns the advertisement. Per RFC 6980 section - // 5, NDP messages cannot be fragmented. Also note that in the common case - // NDP datagrams are very small and ToView() will not incur allocations. - na := header.NDPNeighborAdvert(payload.ToView()) + na := header.NDPNeighborAdvert(h.NDPPayload()) it, err := na.Options().Iter(true) if err != nil { // If we have a malformed NDP NA option, drop the packet. @@ -379,15 +363,14 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P case header.ICMPv6EchoRequest: received.EchoRequest.Increment() - icmpHdr, ok := pkt.Data.PullUp(header.ICMPv6EchoMinimumSize) - if !ok { + if len(v) < header.ICMPv6EchoMinimumSize { received.Invalid.Increment() return } pkt.Data.TrimFront(header.ICMPv6EchoMinimumSize) hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + header.ICMPv6EchoMinimumSize) packet := header.ICMPv6(hdr.Prepend(header.ICMPv6EchoMinimumSize)) - copy(packet, icmpHdr) + copy(packet, h) packet.SetType(header.ICMPv6EchoReply) packet.SetChecksum(header.ICMPv6Checksum(packet, r.LocalAddress, r.RemoteAddress, pkt.Data)) if err := r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, stack.PacketBuffer{ @@ -401,7 +384,7 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P case header.ICMPv6EchoReply: received.EchoReply.Increment() - if pkt.Data.Size() < header.ICMPv6EchoMinimumSize { + if len(v) < header.ICMPv6EchoMinimumSize { received.Invalid.Increment() return } @@ -423,9 +406,8 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P case header.ICMPv6RouterAdvert: received.RouterAdvert.Increment() - // Is the NDP payload of sufficient size to hold a Router - // Advertisement? - if pkt.Data.Size()-header.ICMPv6HeaderSize < header.NDPRAMinimumSize || !isNDPValid() { + p := h.NDPPayload() + if len(p) < header.NDPRAMinimumSize || !isNDPValid() { received.Invalid.Increment() return } @@ -443,11 +425,7 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P return } - // The remainder of payload must be only the router advertisement, so - // payload.ToView() always returns the advertisement. Per RFC 6980 section - // 5, NDP messages cannot be fragmented. Also note that in the common case - // NDP datagrams are very small and ToView() will not incur allocations. - ra := header.NDPRouterAdvert(payload.ToView()) + ra := header.NDPRouterAdvert(p) opts := ra.Options() // Are options valid as per the wire format? diff --git a/pkg/tcpip/network/ipv6/icmp_test.go b/pkg/tcpip/network/ipv6/icmp_test.go index d412ff688..bd099a7f8 100644 --- a/pkg/tcpip/network/ipv6/icmp_test.go +++ b/pkg/tcpip/network/ipv6/icmp_test.go @@ -166,8 +166,7 @@ func TestICMPCounts(t *testing.T) { }, { typ: header.ICMPv6NeighborSolicit, - size: header.ICMPv6NeighborSolicitMinimumSize, - }, + size: header.ICMPv6NeighborSolicitMinimumSize}, { typ: header.ICMPv6NeighborAdvert, size: header.ICMPv6NeighborAdvertMinimumSize, diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go index 486725131..331b0817b 100644 --- a/pkg/tcpip/network/ipv6/ipv6.go +++ b/pkg/tcpip/network/ipv6/ipv6.go @@ -171,11 +171,7 @@ func (*endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuffe // HandlePacket is called by the link layer when new ipv6 packets arrive for // this endpoint. func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { - headerView, ok := pkt.Data.PullUp(header.IPv6MinimumSize) - if !ok { - r.Stats().IP.MalformedPacketsReceived.Increment() - return - } + headerView := pkt.Data.First() h := header.IPv6(headerView) if !h.IsValid(pkt.Data.Size()) { r.Stats().IP.MalformedPacketsReceived.Increment() diff --git a/pkg/tcpip/stack/forwarder_test.go b/pkg/tcpip/stack/forwarder_test.go index c7c663498..e9c652042 100644 --- a/pkg/tcpip/stack/forwarder_test.go +++ b/pkg/tcpip/stack/forwarder_test.go @@ -70,10 +70,7 @@ func (f *fwdTestNetworkEndpoint) ID() *NetworkEndpointID { func (f *fwdTestNetworkEndpoint) HandlePacket(r *Route, pkt PacketBuffer) { // Consume the network header. - b, ok := pkt.Data.PullUp(fwdTestNetHeaderLen) - if !ok { - return - } + b := pkt.Data.First() pkt.Data.TrimFront(fwdTestNetHeaderLen) // Dispatch the packet to the transport protocol. @@ -476,7 +473,7 @@ func TestForwardingWithFakeResolverPartialTimeout(t *testing.T) { t.Fatal("packet not forwarded") } - b := p.Pkt.Data.ToView() + b := p.Pkt.Header.View() if b[0] != 3 { t.Fatalf("got b[0] = %d, want = 3", b[0]) } @@ -520,7 +517,7 @@ func TestForwardingWithFakeResolverTwoPackets(t *testing.T) { t.Fatal("packet not forwarded") } - b := p.Pkt.Data.ToView() + b := p.Pkt.Header.View() if b[0] != 3 { t.Fatalf("got b[0] = %d, want = 3", b[0]) } @@ -567,7 +564,7 @@ func TestForwardingWithFakeResolverManyPackets(t *testing.T) { t.Fatal("packet not forwarded") } - b := p.Pkt.Data.ToView() + b := p.Pkt.Header.View() if b[0] != 3 { t.Fatalf("got b[0] = %d, want = 3", b[0]) } @@ -622,7 +619,7 @@ func TestForwardingWithFakeResolverManyResolutions(t *testing.T) { // The first 5 packets (address 3 to 7) should not be forwarded // because their address resolutions are interrupted. - b := p.Pkt.Data.ToView() + b := p.Pkt.Header.View() if b[0] < 8 { t.Fatalf("got b[0] = %d, want b[0] >= 8", b[0]) } diff --git a/pkg/tcpip/stack/iptables.go b/pkg/tcpip/stack/iptables.go index 6b91159d4..6c0a4b24d 100644 --- a/pkg/tcpip/stack/iptables.go +++ b/pkg/tcpip/stack/iptables.go @@ -212,11 +212,6 @@ func (it *IPTables) Check(hook Hook, pkt PacketBuffer) bool { // CheckPackets runs pkts through the rules for hook and returns a map of packets that // should not go forward. // -// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize. -// -// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a -// precondition. -// // NOTE: unlike the Check API the returned map contains packets that should be // dropped. func (it *IPTables) CheckPackets(hook Hook, pkts PacketBufferList) (drop map[*PacketBuffer]struct{}) { @@ -231,9 +226,7 @@ func (it *IPTables) CheckPackets(hook Hook, pkts PacketBufferList) (drop map[*Pa return drop } -// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize. -// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a -// precondition. +// Precondition: pkt.NetworkHeader is set. func (it *IPTables) checkChain(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) chainVerdict { // Start from ruleIdx and walk the list of rules until a rule gives us // a verdict. @@ -278,21 +271,14 @@ func (it *IPTables) checkChain(hook Hook, pkt PacketBuffer, table Table, ruleIdx return chainDrop } -// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize. -// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a -// precondition. +// Precondition: pk.NetworkHeader is set. func (it *IPTables) checkRule(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) (RuleVerdict, int) { rule := table.Rules[ruleIdx] // If pkt.NetworkHeader hasn't been set yet, it will be contained in - // pkt.Data. + // pkt.Data.First(). if pkt.NetworkHeader == nil { - var ok bool - pkt.NetworkHeader, ok = pkt.Data.PullUp(header.IPv4MinimumSize) - if !ok { - // Precondition has been violated. - panic(fmt.Sprintf("iptables checks require IPv4 headers of at least %d bytes", header.IPv4MinimumSize)) - } + pkt.NetworkHeader = pkt.Data.First() } // Check whether the packet matches the IP header filter. diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go index 8be61f4b1..7b4543caf 100644 --- a/pkg/tcpip/stack/iptables_targets.go +++ b/pkg/tcpip/stack/iptables_targets.go @@ -96,12 +96,9 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { newPkt := pkt.Clone() // Set network header. - headerView, ok := newPkt.Data.PullUp(header.IPv4MinimumSize) - if !ok { - return RuleDrop, 0 - } + headerView := newPkt.Data.First() netHeader := header.IPv4(headerView) - newPkt.NetworkHeader = headerView + newPkt.NetworkHeader = headerView[:header.IPv4MinimumSize] hlen := int(netHeader.HeaderLength()) tlen := int(netHeader.TotalLength()) @@ -120,14 +117,10 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { if newPkt.TransportHeader != nil { udpHeader = header.UDP(newPkt.TransportHeader) } else { - if pkt.Data.Size() < header.UDPMinimumSize { - return RuleDrop, 0 - } - hdr, ok := newPkt.Data.PullUp(header.UDPMinimumSize) - if !ok { + if len(pkt.Data.First()) < header.UDPMinimumSize { return RuleDrop, 0 } - udpHeader = header.UDP(hdr) + udpHeader = header.UDP(newPkt.Data.First()) } udpHeader.SetDestinationPort(rt.MinPort) case header.TCPProtocolNumber: @@ -135,14 +128,10 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { if newPkt.TransportHeader != nil { tcpHeader = header.TCP(newPkt.TransportHeader) } else { - if pkt.Data.Size() < header.TCPMinimumSize { + if len(pkt.Data.First()) < header.TCPMinimumSize { return RuleDrop, 0 } - hdr, ok := newPkt.Data.PullUp(header.TCPMinimumSize) - if !ok { - return RuleDrop, 0 - } - tcpHeader = header.TCP(hdr) + tcpHeader = header.TCP(newPkt.TransportHeader) } // TODO(gvisor.dev/issue/170): Need to recompute checksum // and implement nat connection tracking to support TCP. diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 0c2b1f36a..016dbe15e 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -1203,12 +1203,12 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link n.stack.stats.IP.PacketsReceived.Increment() } - netHeader, ok := pkt.Data.PullUp(netProto.MinimumPacketSize()) - if !ok { + if len(pkt.Data.First()) < netProto.MinimumPacketSize() { n.stack.stats.MalformedRcvdPackets.Increment() return } - src, dst := netProto.ParseAddresses(netHeader) + + src, dst := netProto.ParseAddresses(pkt.Data.First()) if n.stack.handleLocal && !n.isLoopback() && n.getRef(protocol, src) != nil { // The source address is one of our own, so we never should have gotten a @@ -1289,8 +1289,22 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link func (n *NIC) forwardPacket(r *Route, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) { // TODO(b/143425874) Decrease the TTL field in forwarded packets. - if linkHeaderLen := int(n.linkEP.MaxHeaderLength()); linkHeaderLen != 0 { - pkt.Header = buffer.NewPrependable(linkHeaderLen) + + firstData := pkt.Data.First() + pkt.Data.RemoveFirst() + + if linkHeaderLen := int(n.linkEP.MaxHeaderLength()); linkHeaderLen == 0 { + pkt.Header = buffer.NewPrependableFromView(firstData) + } else { + firstDataLen := len(firstData) + + // pkt.Header should have enough capacity to hold n.linkEP's headers. + pkt.Header = buffer.NewPrependable(firstDataLen + linkHeaderLen) + + // TODO(b/151227689): avoid copying the packet when forwarding + if n := copy(pkt.Header.Prepend(firstDataLen), firstData); n != firstDataLen { + panic(fmt.Sprintf("copied %d bytes, expected %d", n, firstDataLen)) + } } if err := n.linkEP.WritePacket(r, nil /* gso */, protocol, pkt); err != nil { @@ -1318,13 +1332,12 @@ func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolN // validly formed. n.stack.demux.deliverRawPacket(r, protocol, pkt) - transHeader, ok := pkt.Data.PullUp(transProto.MinimumPacketSize()) - if !ok { + if len(pkt.Data.First()) < transProto.MinimumPacketSize() { n.stack.stats.MalformedRcvdPackets.Increment() return } - srcPort, dstPort, err := transProto.ParsePorts(transHeader) + srcPort, dstPort, err := transProto.ParsePorts(pkt.Data.First()) if err != nil { n.stack.stats.MalformedRcvdPackets.Increment() return @@ -1362,12 +1375,11 @@ func (n *NIC) DeliverTransportControlPacket(local, remote tcpip.Address, net tcp // ICMPv4 only guarantees that 8 bytes of the transport protocol will // be present in the payload. We know that the ports are within the // first 8 bytes for all known transport protocols. - transHeader, ok := pkt.Data.PullUp(8) - if !ok { + if len(pkt.Data.First()) < 8 { return } - srcPort, dstPort, err := transProto.ParsePorts(transHeader) + srcPort, dstPort, err := transProto.ParsePorts(pkt.Data.First()) if err != nil { return } diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go index 7d36f8e84..dc125f25e 100644 --- a/pkg/tcpip/stack/packet_buffer.go +++ b/pkg/tcpip/stack/packet_buffer.go @@ -37,13 +37,7 @@ type PacketBuffer struct { Data buffer.VectorisedView // Header holds the headers of outbound packets. As a packet is passed - // down the stack, each layer adds to Header. Note that forwarded - // packets don't populate Headers on their way out -- their headers and - // payload are never parsed out and remain in Data. - // - // TODO(gvisor.dev/issue/170): Forwarded packets don't currently - // populate Header, but should. This will be doable once early parsing - // (https://github.com/google/gvisor/pull/1995) is supported. + // down the stack, each layer adds to Header. Header buffer.Prependable // These fields are used by both inbound and outbound packets. They diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index d45d2cc1f..c7634ceb1 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -95,18 +95,16 @@ func (f *fakeNetworkEndpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffe f.proto.packetCount[int(f.id.LocalAddress[0])%len(f.proto.packetCount)]++ // Consume the network header. - b, ok := pkt.Data.PullUp(fakeNetHeaderLen) - if !ok { - return - } + b := pkt.Data.First() pkt.Data.TrimFront(fakeNetHeaderLen) // Handle control packets. if b[2] == uint8(fakeControlProtocol) { - nb, ok := pkt.Data.PullUp(fakeNetHeaderLen) - if !ok { + nb := pkt.Data.First() + if len(nb) < fakeNetHeaderLen { return } + pkt.Data.TrimFront(fakeNetHeaderLen) f.dispatcher.DeliverTransportControlPacket(tcpip.Address(nb[1:2]), tcpip.Address(nb[0:1]), fakeNetNumber, tcpip.TransportProtocolNumber(nb[2]), stack.ControlPortUnreachable, 0, pkt) return diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go index a611e44ab..3084e6593 100644 --- a/pkg/tcpip/stack/transport_test.go +++ b/pkg/tcpip/stack/transport_test.go @@ -642,11 +642,10 @@ func TestTransportForwarding(t *testing.T) { t.Fatal("Response packet not forwarded") } - hdrs := p.Pkt.Data.ToView() - if dst := hdrs[0]; dst != 3 { + if dst := p.Pkt.Header.View()[0]; dst != 3 { t.Errorf("Response packet has incorrect destination addresss: got = %d, want = 3", dst) } - if src := hdrs[1]; src != 1 { + if src := p.Pkt.Header.View()[1]; src != 1 { t.Errorf("Response packet has incorrect source addresss: got = %d, want = 3", src) } } diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go index b1d820372..feef8dca0 100644 --- a/pkg/tcpip/transport/icmp/endpoint.go +++ b/pkg/tcpip/transport/icmp/endpoint.go @@ -747,15 +747,15 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pk // Only accept echo replies. switch e.NetProto { case header.IPv4ProtocolNumber: - h, ok := pkt.Data.PullUp(header.ICMPv4MinimumSize) - if !ok || header.ICMPv4(h).Type() != header.ICMPv4EchoReply { + h := header.ICMPv4(pkt.Data.First()) + if h.Type() != header.ICMPv4EchoReply { e.stack.Stats().DroppedPackets.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() return } case header.IPv6ProtocolNumber: - h, ok := pkt.Data.PullUp(header.ICMPv6MinimumSize) - if !ok || header.ICMPv6(h).Type() != header.ICMPv6EchoReply { + h := header.ICMPv6(pkt.Data.First()) + if h.Type() != header.ICMPv6EchoReply { e.stack.Stats().DroppedPackets.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() return diff --git a/pkg/tcpip/transport/tcp/segment.go b/pkg/tcpip/transport/tcp/segment.go index 7712ce652..40461fd31 100644 --- a/pkg/tcpip/transport/tcp/segment.go +++ b/pkg/tcpip/transport/tcp/segment.go @@ -144,11 +144,7 @@ func (s *segment) logicalLen() seqnum.Size { // TCP checksum and stores the checksum and result of checksum verification in // the csum and csumValid fields of the segment. func (s *segment) parse() bool { - h, ok := s.data.PullUp(header.TCPMinimumSize) - if !ok { - return false - } - hdr := header.TCP(h) + h := header.TCP(s.data.First()) // h is the header followed by the payload. We check that the offset to // the data respects the following constraints: @@ -160,16 +156,12 @@ func (s *segment) parse() bool { // N.B. The segment has already been validated as having at least the // minimum TCP size before reaching here, so it's safe to read the // fields. - offset := int(hdr.DataOffset()) - if offset < header.TCPMinimumSize { - return false - } - hdrWithOpts, ok := s.data.PullUp(offset) - if !ok { + offset := int(h.DataOffset()) + if offset < header.TCPMinimumSize || offset > len(h) { return false } - s.options = []byte(hdrWithOpts[header.TCPMinimumSize:]) + s.options = []byte(h[header.TCPMinimumSize:offset]) s.parsedOptions = header.ParseTCPOptions(s.options) // Query the link capabilities to decide if checksum validation is @@ -181,19 +173,18 @@ func (s *segment) parse() bool { s.data.TrimFront(offset) } if verifyChecksum { - hdr = header.TCP(hdrWithOpts) - s.csum = hdr.Checksum() + s.csum = h.Checksum() xsum := s.route.PseudoHeaderChecksum(ProtocolNumber, uint16(s.data.Size())) - xsum = hdr.CalculateChecksum(xsum) + xsum = h.CalculateChecksum(xsum) s.data.TrimFront(offset) xsum = header.ChecksumVV(s.data, xsum) s.csumValid = xsum == 0xffff } - s.sequenceNumber = seqnum.Value(hdr.SequenceNumber()) - s.ackNumber = seqnum.Value(hdr.AckNumber()) - s.flags = hdr.Flags() - s.window = seqnum.Size(hdr.WindowSize()) + s.sequenceNumber = seqnum.Value(h.SequenceNumber()) + s.ackNumber = seqnum.Value(h.AckNumber()) + s.flags = h.Flags() + s.window = seqnum.Size(h.WindowSize()) return true } diff --git a/pkg/tcpip/transport/tcp/tcp_test.go b/pkg/tcpip/transport/tcp/tcp_test.go index 286c66cf5..ab1014c7f 100644 --- a/pkg/tcpip/transport/tcp/tcp_test.go +++ b/pkg/tcpip/transport/tcp/tcp_test.go @@ -3548,7 +3548,7 @@ func TestReceivedInvalidSegmentCountIncrement(t *testing.T) { AckNum: c.IRS.Add(1), RcvWnd: 30000, }) - tcpbuf := vv.ToView()[header.IPv4MinimumSize:] + tcpbuf := vv.First()[header.IPv4MinimumSize:] tcpbuf[header.TCPDataOffset] = ((header.TCPMinimumSize - 1) / 4) << 4 c.SendSegment(vv) @@ -3575,7 +3575,7 @@ func TestReceivedIncorrectChecksumIncrement(t *testing.T) { AckNum: c.IRS.Add(1), RcvWnd: 30000, }) - tcpbuf := vv.ToView()[header.IPv4MinimumSize:] + tcpbuf := vv.First()[header.IPv4MinimumSize:] // Overwrite a byte in the payload which should cause checksum // verification to fail. tcpbuf[(tcpbuf[header.TCPDataOffset]>>4)*4] = 0x4 diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index 756ab913a..edb54f0be 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -1250,8 +1250,8 @@ func (e *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask { // endpoint. func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt stack.PacketBuffer) { // Get the header then trim it from the view. - hdr, ok := pkt.Data.PullUp(header.UDPMinimumSize) - if !ok || int(header.UDP(hdr).Length()) > pkt.Data.Size() { + hdr := header.UDP(pkt.Data.First()) + if int(hdr.Length()) > pkt.Data.Size() { // Malformed packet. e.stack.Stats().UDP.MalformedPacketsReceived.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() @@ -1286,7 +1286,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pk senderAddress: tcpip.FullAddress{ NIC: r.NICID(), Addr: id.RemoteAddress, - Port: header.UDP(hdr).SourcePort(), + Port: hdr.SourcePort(), }, } packet.data = pkt.Data diff --git a/pkg/tcpip/transport/udp/protocol.go b/pkg/tcpip/transport/udp/protocol.go index 52af6de22..6e31a9bac 100644 --- a/pkg/tcpip/transport/udp/protocol.go +++ b/pkg/tcpip/transport/udp/protocol.go @@ -68,13 +68,8 @@ func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) { // that don't match any existing endpoint. func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt stack.PacketBuffer) bool { // Get the header then trim it from the view. - h, ok := pkt.Data.PullUp(header.UDPMinimumSize) - if !ok { - // Malformed packet. - r.Stack().Stats().UDP.MalformedPacketsReceived.Increment() - return true - } - if int(header.UDP(h).Length()) > pkt.Data.Size() { + hdr := header.UDP(pkt.Data.First()) + if int(hdr.Length()) > pkt.Data.Size() { // Malformed packet. r.Stack().Stats().UDP.MalformedPacketsReceived.Increment() return true |